Great Pack Debate: Pros & Cons of ULA Circuit Vs Osprey Viva

Apparently, I wasn’t quite done with the Great Pack Debate. In my last post, I talked about how reducing my base weight was the answer to my pack dilemma. However, packs just kept coming back to haunt me. People kept posting comments about Osprey packs, and the comment by guy #4 at the outdoor gear store, about going for the heavier pack to be comfortable over being super light weight, kept resurfacing in my mind.

Everyone loves a Pro/Con list

This has become an impossible decision, so I’ve decided to write out the pros and cons of each pack:

ULA Circuit



  • Ultra light weight
  • Hand straps and water bottle bungees on shoulder straps
  • Big side pockets that easily fit my 2L HydraPaks
  • Big mesh pocket on the back with a bungee to hang stuff from
  • Fits my Bear Vault (BV500)
  • I already own it



  • My total weight is likely to be over the suggested 30lbs rating
  • The hip belt doesn’t fit right and needs to be replaced
  • Only one way into the pack
  • No quick access pockets on the pack for stuff like headlamp, maps, and gloves
  • The padding is not super comfortable
  • The sternum strap irritates my chest when I get hot
  • Only a few extra attachment points on the outside

Osprey Viva 65



  • Can handle loads up to 50lbs
  • Floating top pocket for quick access stuff
  • Lots of attachment points on the outside, including on the shoulder straps where I could attach hand straps
  • Big stretch mesh pocket on the back
  • Separate zippered compartment for sleeping bag with detachable divider
  • Fits my Bear Vault
  • Will be able to hold all my gear
  • Hip belt can be adjusted on the fly
  • Padding is super comfortable
  • The sternum strap doesn’t touch my chest



  • 1.3 lbs heavier than the Circuit
  • It’s an extra cost to buy
  • I could potentially load it with 50lbs
  • I’m not sure if my 2L HydraPaks will fit in the side pockets
  • No water bottle bungees on the shoulder straps

Definitely do a Pro/Con list!

This was an extremely helpful exercise, as it forced me to look at the specific details of what each pack did and didn’t have to offer. If you’re having trouble making a gear decision, I highly recommend writing out a list like this to help you see each piece of gear more clearly, and what it is about the gear that you like/dislike, want/don’t want, and need/don’t need.

So, will it be the ULA Circuit or the Osprey Viva 65?


I already have the Osprey pack on hold at the gear store until Friday, but I think I will get it, try it, and then decide which it will be. I’m pretty sure, however, I’m going to go with the Osprey. I think…

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Comments 10

  • George : Feb 11th

    I just want to put this out there. You may carry over 30 pounds, but you’re unlikely to carry over 30 for long. Your pack gets lighter every day

    • Annette : Feb 14th

      That’s a good point. Something I can keep in mind on those days my pack feels really heavy!

  • Luna : Feb 11th

    The separate access point for the sleeping bag is not useful when thru hiking, because the only time you’ll be getting your sleeping bag out is the end of the day, when you’re pack is already unloaded. The divider between the sleeping bag compartment and the body of the pack creates wasted space, and extra weight.

    You will chafe at some point, somewhere, regardless of which pack you’re using. You’ll endure. The sternum strap on your ula pack may not rub anymore once you get a hip belt that fits. The hip belt is probably the most important part of the pack. It needs to fit snug to support the majority of the load in your pack.

    • Annette : Feb 14th

      Thank you for your comments. I know that experience is the best way to gain knowledge on gear.

  • Andrew : Feb 12th

    I agree with the 1st two comments!

    I think the Circuit can handle the times you’d be above 30lbs fine, just get the hipbelt that fits correctly. ULA has great customer service.

    On my ULA CDT, I currently use the mesh back pocket and belt pockets for my quick access stuff. I do, though, have a pack lid coming from Luke’s Ultralight that will hold most of that stuff and free up some room in the mesh and I side of my pack. It will cost much less than the Osprey pack! $45 and 1oz for the standard build, and it matches the pack fabric!

    I bought ZPacks add on shoulder strap pads for my CDT, and they are great. Can’t help with the other padding, as the CDT has none!

    You shouldn’t need to strap that much to the outside of your pack…..

    Sleeping bag dividers are worthless, I always end up leaving it all open any way, and the extra materials is unneeded weight.

    Good luck!

    • Annette : Feb 14th

      Thank you. Good to know. I wish I’d known more when I bought the Circuit. I’ll definitely check out the pack lid you mentioned. I don’t find the hip pockets enough for all the quick grab stuff I would have. It would also be great if free shipping were offered outside the US.

  • Michael Allison : Feb 24th

    Take a look at the Deuter Act Zero pack weighing in 3 lbs. Lots of pading and very cool on your back. Deuter is one of the most underrated packs in the outdoor market. A separate sleeping bag compartment is useless and adds weight.

  • Aaron Owens : Mar 24th

    I had this very dilemma today as I packed my Gregory Jade 63 one last time in preparation for my flight to San Diego TOMORROW. Using my Exos 58 for the majority of my PCT trek but it’s not going to cut it in the Sierra this year as I plan to enter in May. Got the same schpeel from the REI guy about ultralight vs the comfort of a heavier pack. Traded up for an even beefier pack, Gregory Deva 60, as the Jade (40 lb max carry) couldn’t handle the weight. The Deva is so much more comfortable despite the additional pack weight. I think I’ll be more comfortable and enjoy the trek more with the Deva. Hope whatever you chose works out for you. Happy trails!

    • Annette : Mar 24th

      Thanks Aaron! I’ve decided to use the Osprey Viva. I’ve carried up to 37lbs in it and it was still comfortable. I’m very happy with it. I’m not writing off the Circuit, however. If my needs change, I’ll get it sent to me on the trail. Have an amazing time! I’ll be on my way in 25 days :).

  • bill : Sep 1st

    Thank you for the Nice Pro n Con list ! … For sure an extra bit of weight in the pack itself is worth it IF it makes the hike comfortable.

    * The bottom divided area is more useful for a tent, or a down vest, jacket and food, since they all come out before the sleeping bag anyway.
    * A bear canister should fit sideways in a pack. (Bear spray is not needed unless you are in grizzly country.)
    * Dangly jangly things outside a pack is not cool. Pack it !
    * Side pockets should hold lighter items, not filled water jugs… keep that weight central ! use the bladder.
    * Get really light and minimal in the Contents first, then choose a pack that fits, ( and in a color that doesn’t look lame after 2 years ).
    * Back breathability is very helpful, sweaty no bueno.


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